glScissor

hi,
i want to know the usual ways to “forbid” opengl to render stuff which is outside of the screen to get more speed(why should i render invisible things anyway?)
i read about glScissor but i can’t figure it out.
just let me know how you do it,thanks

glScissor() is used to clip a region in the viewport. OpenGL will automatically clip anything that is trying to be drawn outside of the viewport set by glViewport().

I’ve found glScissor to be kind of redundant, glViewport does everything I need.
fs
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